Organs in humans and animals are composed of tissues, which in turn are composed of cells. Epithelial tissue covers body surfaces and lines body cavities. Endothelial cells perform a similar role in forming a lining layer in tissues, such as blood vessels, lymph tissues, and urogenital system. Connective tissue cells maintain cohesiveness between cells, and act as a “scaffold” in both normal tissues and as part of the repair cell process. Inflammatory cells, such as lymphocytes, macrophages, and neutrophils, are part of the normal repair process as well as removers of infectious agents. Epithelial, endothelial, connective tissue, and inflammatory cells are therefore important for the defense, normal structure, and repair of mammalian animals, including protecting the internal environment of the body against the external environment, and containing fluids in various organs.
Such organs of the human or animal body include the gastrointestinal system, which in turn includes the stomach and the small and large intestines. Eaten food is collected in the stomach, whereupon it is digested in the duodenum portion of the small intestines, and then passed on to the jejunum and ileum portion of the small intestines where the nutrients (e.g., fatty acids, sugars, amino acids) from the digested food are absorbed. The remaining digesta is then passed along to the large intestine (sometimes called the “bowel” or “gut”) in which fluids from this solid mass of digested food are absorbed. The leftover, used portion of the food enters the rectum for subsequent discharge from the body.
The epithelial tissue lining of the gastrointestinal tract possess the remarkable ability to remain intact despite being constantly bathed in acid and proteolytic enzymes that can digest virtually any form of food that is eaten. When a superficial mucosal injury occurs, such as following direct physical trauma or ingestion of noxious agents like aspirin or alcohol, it is rapidly healed. This healing process is achieved through migration of surviving cells around the wound edge to cover the denuded area of the tissue within the first hour after the injury, followed by differentiation and multiplication (“proliferation”) of the cells beginning one to two days after the injury. Finally, remodeling occurs where the mucosa slowly re-establishes an essentially normal looking mucosa. The intestines therefore possess powerful mucosal defense and repair mechanisms.
In general, an ulcer is any eroded area of the skin or mucous membrane marked by tissue disintegration. More commonly, however, ulcer is used to refer to disorders in the upper digestive tract. It is estimated that approximately 10% of the United States population will develop an ulcer at some point in their lives. Peptic ulcers can develop in the lower part of the esophagus, the stomach, and the duodenum and jejunum portions of the small intestines. Peptic ulcers are caused by infection by Helicobacter Pylori bacteria; nonsteroidal anti-inflammatory drugs (NSAIDs) like aspirin, ibuprofen, flurbiprofen, ketoprofen, and indomethacin; and disorders like Zollinger-Ellison syndrome that cause over-secretion of stomach juices. Symptoms for such peptic ulcers include heartburn, stomach pain relieved by eating or antacids, weight gain, and a burning sensation at the back of the throat.
Gastric ulcers account for about 16% of peptic ulcers, and are most commonly caused by the use of NSAIDs, or by Helicobacter infection. Symptoms of gastric ulcers include feelings of indigestion and heartburn, weight loss, and repeated episodes of gastrointestinal bleeding.
About 5% of ulcer patients actually develop perforations, which are holes in the duodenal or gastric wall through which the stomach contents can leak out into the abdominal cavity. Emergency surgery may be required to treat such a perforation.
Fortunately, however, most peptic and gastric ulcers can be medicated with drugs to create chemical reactions that either lower the rate of stomach acid secretion, or protect the mucous tissues that line the digestive tract. Such antisecretory drugs include: proton pump inhibitors, which bind an enzyme that secretes stomach acid, like omeprazole (Prilosec) and lansoprazole (Prevacid); or H2 receptor antagonists like ranitidine (Zantac), cimetidine (Tagamet), famotidine (Pepcid), or nizatidine (Axid). Drugs currently used to protect the stomach tissues include sucralfate (Carafate), bismuth preparations, and misoprostol (Cytotec). These drugs act to neutralize disorders like excessive acid secretion that would otherwise interfere with the natural function of cell migration and proliferation to heal the ulcer.
It has been found, however, that alternative treatments using bioactive agents instead of traditional drug chemicals can effectively treat ulcers by rebalancing the stomach's hydrochloric acid output, and/or enhancing the mucosal lining of the stomach and intestines through promotion of these natural cell migration and proliferation functions. Such bioactive agents include plant extracts like aloe vera, deglycrrhizinated licorice (DGL) in a chewable or powder form, raw cabbage juice, substances of animal origin, artificially produced nutritional molecules like zinc-carnisine, and artificially made normal proteins like recombinant human spasmolytic polypeptide (hSP). One particularly important example of an animal-originated bioactive agent is colostrum, which is the first milk produced after birth, and has been shown to enhance the cell migration and growth healing function of ulcerated digestive tracts caused by NSAIDs. See Playford, R. J., Floyd, D. N., MacDonald, C. E. et al., “Bovine Colostrum in a Health Food Supplement Which Prevents NSAID—Induced Gut Damage,” Gut 44: 653-58 (1999); Playford, R. J., MacDonald, C. E., Calnan, D. P. et al., “Colostrum, Reduces the Acute, Non-Steroidal, Anti-Inflammatory Drug-Induced Increase In Intestinal Permeability,” Clinical Science 100: 627-33 (2001). Similarly, another study has shown that hSP may be used to enhance cell migration in order to reduce gastric damage by 50%. See Playford, R. J., Marchblank, T., Chinery, R. et al., “Human Spasmolytic Polypeptide Is A Cytoprotective Agent That Stimulates Cell Migration,” Gastroenterology 108: 108-16 (1995). Zinc-Carnisine manufactured by Lonza Inc. of Allendale, N.J. may also be used to treat stomach ulcers and gastric reflux.
Ghosh, S. and Playford, R. J., “Bioactive Natural Compounds for the Treatment of Gastrointestinal Disorders”, Clinical Science 104, 547-56 (2003), provides a survey of many other bioactive compounds that have been found useful for the treatment of various gastrointestinal disorders. For example, curcumin capsules improve endoscopic healing of peptic ulcers, as well as improving symptoms of patients with non-ulcer dyspepsia. Sangre de grado has also been shown to heal experimental gastric ulcers induced by application of 80% acetic acids in rats. Moreover, acemannan, a component of aloe vera, prevents stress-induced gastric ulceration in rats.
Other organs within the human or animal body share the same natural cell migration, proliferation, inflammation, and other healing functions for addressing an injury to the epithelial, endothelial, or connective tissue, and which can also be influenced directly or indirectly by bioactive products. For example, mouse ear or rat hind paw inflamed by the application of croton oil was helped by the topical application of aloe gel. Similarly, topical honey has been shown to be effective in treating postoperative skin wounds in neonates that had failed to respond to antibiotic therapy. Acemannan has been reported to accelerate healing and reduce pain in aphthous stomatitis. Milk whey has exhibited beneficial effects for patients with chemical-induced corrosive injuries. Comeal abrasions of the eye may be treated with bioactive agents like epidermal growth factor (EGF) or hSP. If these bioactive products are to be used effectively to influence such processes in a reliable manner, then it is important that consistency and accuracy in quality control is provided. Bioactive products, particularly mixed protein constituents like bovine calf serum, are vital additives for the long-term maintenance of mammalian cells grown in laboratory cultures, e.g., for production of antibodies. Reduction of the variation in biological activity of these additives is therefore highly desirable for allowing stability of these cells over time.
Currently, manufacturers measure amounts of constituents such as levels of total protein or immunoglobulins in colostrum or total amount of chemical constituents in other products as a crude indicator of their predicted effectiveness. Unfortunately, this approach for measuring the bioeffectiveness of the active ingredients in these bioactive agents has a number of shortcomings. For example, it disregards the fact that biological activity in a composition may decrease over time due to factors like oxidation or degradation of proteins. Thus, the same sample of a bioactive agent may exhibit different levels of enhancement of cell migration or cell proliferation function between two different days. Likewise, two different preparations of the same type of the bioactive agent may exhibit differing levels of cell migration or cell proliferation enhancement when tested the same day. Moreover, for many neutraceuticals, the factors that are causing the biological activity are incompletely understood or identified, so a characteristic like total protein may turn out to be irrelevant to the composition's biological activity.
Being able to accurately characterize biological activity therefore would be very advantageous to both manufacturers and end users by showing that a commercial product is truly active, and that a standardized product is being manufactured. Furthermore, a characterization method for biological activity that is reproducible and permits comparison of different lots of the same bioactive agent or different bioactive agents altogether would provide a great benefit.